From: Michael Ellerman <mpe@ellerman•id.au>
To: Leonardo Bras <leonardo@linux•ibm.com>
Cc: Leonardo Bras <leonardo@linux•ibm.com>,
Paul Mackerras <paulus@samba•org>,
linuxppc-dev@lists•ozlabs.org, linux-kernel@vger•kernel.org
Subject: Re: [RFC PATCH] Replaces long number representation by BIT() macro
Date: Wed, 03 Jul 2019 01:19:34 +1000 [thread overview]
Message-ID: <87imskihvd.fsf@concordia.ellerman.id.au> (raw)
In-Reply-To: <20190613180227.29558-1-leonardo@linux.ibm.com>
Hi Leonardo,
Leonardo Bras <leonardo@linux•ibm.com> writes:
> The main reason of this change is to make these bitmasks more readable.
>
> The macro ASM_CONST() just appends an UL to it's parameter, so it can be
> easily replaced by BIT_MASK, that already uses a UL representation.
>
> ASM_CONST() in this file may behave different if __ASSEMBLY__ is defined,
> as it is used on .S files, just leaving the parameter as is.
Thanks for the patch, but I don't consider this an improvement in
readability.
At boot we print the firmware features, eg:
firmware_features = 0x00000001c45ffc5f
And it's much easier to match that up to the full constants, than to the
bit numbers.
Similarly in memory or register dumps.
What we could do is switch to the `UL` macro from include/linux/const.h,
rather than using our own ASM_CONST.
cheers
> diff --git a/arch/powerpc/include/asm/firmware.h b/arch/powerpc/include/asm/firmware.h
> index 00bc42d95679..7a5b0cc0bc85 100644
> --- a/arch/powerpc/include/asm/firmware.h
> +++ b/arch/powerpc/include/asm/firmware.h
> @@ -14,46 +14,45 @@
>
> #ifdef __KERNEL__
>
> -#include <asm/asm-const.h>
> -
> +#include <linux/bits.h>
> /* firmware feature bitmask values */
>
> -#define FW_FEATURE_PFT ASM_CONST(0x0000000000000001)
> -#define FW_FEATURE_TCE ASM_CONST(0x0000000000000002)
> -#define FW_FEATURE_SPRG0 ASM_CONST(0x0000000000000004)
> -#define FW_FEATURE_DABR ASM_CONST(0x0000000000000008)
> -#define FW_FEATURE_COPY ASM_CONST(0x0000000000000010)
> -#define FW_FEATURE_ASR ASM_CONST(0x0000000000000020)
> -#define FW_FEATURE_DEBUG ASM_CONST(0x0000000000000040)
> -#define FW_FEATURE_TERM ASM_CONST(0x0000000000000080)
> -#define FW_FEATURE_PERF ASM_CONST(0x0000000000000100)
> -#define FW_FEATURE_DUMP ASM_CONST(0x0000000000000200)
> -#define FW_FEATURE_INTERRUPT ASM_CONST(0x0000000000000400)
> -#define FW_FEATURE_MIGRATE ASM_CONST(0x0000000000000800)
> -#define FW_FEATURE_PERFMON ASM_CONST(0x0000000000001000)
> -#define FW_FEATURE_CRQ ASM_CONST(0x0000000000002000)
> -#define FW_FEATURE_VIO ASM_CONST(0x0000000000004000)
> -#define FW_FEATURE_RDMA ASM_CONST(0x0000000000008000)
> -#define FW_FEATURE_LLAN ASM_CONST(0x0000000000010000)
> -#define FW_FEATURE_BULK_REMOVE ASM_CONST(0x0000000000020000)
> -#define FW_FEATURE_XDABR ASM_CONST(0x0000000000040000)
> -#define FW_FEATURE_MULTITCE ASM_CONST(0x0000000000080000)
> -#define FW_FEATURE_SPLPAR ASM_CONST(0x0000000000100000)
> -#define FW_FEATURE_LPAR ASM_CONST(0x0000000000400000)
> -#define FW_FEATURE_PS3_LV1 ASM_CONST(0x0000000000800000)
> -#define FW_FEATURE_HPT_RESIZE ASM_CONST(0x0000000001000000)
> -#define FW_FEATURE_CMO ASM_CONST(0x0000000002000000)
> -#define FW_FEATURE_VPHN ASM_CONST(0x0000000004000000)
> -#define FW_FEATURE_XCMO ASM_CONST(0x0000000008000000)
> -#define FW_FEATURE_OPAL ASM_CONST(0x0000000010000000)
> -#define FW_FEATURE_SET_MODE ASM_CONST(0x0000000040000000)
> -#define FW_FEATURE_BEST_ENERGY ASM_CONST(0x0000000080000000)
> -#define FW_FEATURE_TYPE1_AFFINITY ASM_CONST(0x0000000100000000)
> -#define FW_FEATURE_PRRN ASM_CONST(0x0000000200000000)
> -#define FW_FEATURE_DRMEM_V2 ASM_CONST(0x0000000400000000)
> -#define FW_FEATURE_DRC_INFO ASM_CONST(0x0000000800000000)
> -#define FW_FEATURE_BLOCK_REMOVE ASM_CONST(0x0000001000000000)
> -#define FW_FEATURE_PAPR_SCM ASM_CONST(0x0000002000000000)
> +#define FW_FEATURE_PFT BIT(0)
> +#define FW_FEATURE_TCE BIT(1)
> +#define FW_FEATURE_SPRG0 BIT(2)
> +#define FW_FEATURE_DABR BIT(3)
> +#define FW_FEATURE_COPY BIT(4)
> +#define FW_FEATURE_ASR BIT(5)
> +#define FW_FEATURE_DEBUG BIT(6)
> +#define FW_FEATURE_TERM BIT(7)
> +#define FW_FEATURE_PERF BIT(8)
> +#define FW_FEATURE_DUMP BIT(9)
> +#define FW_FEATURE_INTERRUPT BIT(10)
> +#define FW_FEATURE_MIGRATE BIT(11)
> +#define FW_FEATURE_PERFMON BIT(12)
> +#define FW_FEATURE_CRQ BIT(13)
> +#define FW_FEATURE_VIO BIT(14)
> +#define FW_FEATURE_RDMA BIT(15)
> +#define FW_FEATURE_LLAN BIT(16)
> +#define FW_FEATURE_BULK_REMOVE BIT(17)
> +#define FW_FEATURE_XDABR BIT(18)
> +#define FW_FEATURE_MULTITCE BIT(19)
> +#define FW_FEATURE_SPLPAR BIT(20)
> +#define FW_FEATURE_LPAR BIT(22)
> +#define FW_FEATURE_PS3_LV1 BIT(23)
> +#define FW_FEATURE_HPT_RESIZE BIT(24)
> +#define FW_FEATURE_CMO BIT(25)
> +#define FW_FEATURE_VPHN BIT(26)
> +#define FW_FEATURE_XCMO BIT(27)
> +#define FW_FEATURE_OPAL BIT(28)
> +#define FW_FEATURE_SET_MODE BIT(30)
> +#define FW_FEATURE_BEST_ENERGY BIT(31)
> +#define FW_FEATURE_TYPE1_AFFINITY BIT(32)
> +#define FW_FEATURE_PRRN BIT(33)
> +#define FW_FEATURE_DRMEM_V2 BIT(34)
> +#define FW_FEATURE_DRC_INFO BIT(35)
> +#define FW_FEATURE_BLOCK_REMOVE BIT(36)
> +#define FW_FEATURE_PAPR_SCM BIT(37)
>
> #ifndef __ASSEMBLY__
>
> --
> 2.17.1
next prev parent reply other threads:[~2019-07-02 15:21 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-13 18:02 [RFC PATCH] Replaces long number representation by BIT() macro Leonardo Bras
2019-06-13 20:24 ` Leonardo Bras
2019-07-02 15:19 ` Michael Ellerman [this message]
2019-07-02 16:16 ` Segher Boessenkool
2019-07-02 16:48 ` Segher Boessenkool
2019-07-07 13:15 ` Michael Ellerman
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